Calculate the number of coulombs required to deposit 40 . 5 g of Al when the electrode reaction is Al 3 + + 3 e - → Al ( s ) .

Electrode reaction : Al 3 + + 3 e - → Al ( s ) Given : Weight of aluminium to be deposited = 40 . 5 g Solution : Number of electrons exchanged in 1 mol n = 3 Amount of charge deposited q = n × F Amount of charge required to deposit 1 mol of Al = 3 × 96500 Amount of charge required to deposit 1 g of Al = 3 × 96500 27 . 0 Amount of charge required to deposit 40 . 5 g of Al = 3 × 96500 × 40 . 5 27 = 434250 C Thus, 434250 coulombs are required to deposit 40 . 5 g of aluminium.

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A certain metal salt solutions is electrolysed in series with a silver coulometer. The weights of silver and the metal deposited are 0.5094 g and 0.2653 g. Calculate the valency of the metal if its atomic weight is nearly that of silver.

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Two Faraday of electricity is passed through a solution of

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Chemistry>Physical Chemistry>Electrochemistry>Electrolytic cells

The number of moles of electrons passed when a current of

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Chemistry>Physical Chemistry>Electrochemistry>Electrolytic cells

A constant current (0.5 amp) is passed for 1 hour through (i) aqueous

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, separately. The ratio of the mass of the metals deposited on the cathode is

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Chemistry>Physical Chemistry>Electrochemistry>Electrolytic cells

Calculate the number of coulombs required to deposit

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when the electrode reaction is

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Chemistry>Physical Chemistry>Electrochemistry>Electrolytic cells

When an electric current is passed through acidified water, 112 mL of hydrogen gas at N.T.P was collected at the cathode in 965 seconds. The current passed, in ampere, is:

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Chemistry>Physical Chemistry>Electrochemistry>Electrolytic cells

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Chemistry>Physical Chemistry>Electrochemistry>Electrolytic cells

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250 s

through

250 m L of 0.15 M

solution of

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Only

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of the current was utilised for electrolysis. The molarity of

M S O_{4}

solution after electrolysis is closest to [Assume that the volume of the solution remain constant]

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State Faraday's first law of electrolysis.

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Chemistry>Physical Chemistry>Electrochemistry>Electrolytic cells

State Faraday's second law of electrolysis.

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Chemistry>Physical Chemistry>Electrochemistry>Electrolytic cells

When 9.65 ampere current was passed for 1.0 hour into nitrobenzene in acidic medium, the amount of p-aminophenol produced is:

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Chemistry>Physical Chemistry>Electrochemistry>Electrolytic cells

The quantity of electricity needed to separately electrolyse

1 M

solution of

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and

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completely is in the ratio of

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Chemistry>Physical Chemistry>Electrochemistry>Electrolytic cells

During the electrolysis of molten sodium chloride, the time required to produce

0.10 mol

of chlorine gas using a current of

3 amperes

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Chemistry>Physical Chemistry>Electrochemistry>Electrolytic cells

The anodic half-cell of lead-acid battery is recharged using electricity of

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electrolyzed in

g

during the process is: (Molar mass of

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)

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Chemistry>Physical Chemistry>Electrochemistry>Electrolytic cells

The number of electrons delivered at the cathode, during electrolysis by a current of

1 ampere in 60 seconds

is (charge on electron

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Chemistry>Physical Chemistry>Electrochemistry>Electrolytic cells

The density of metal and equivalent weight of a metal are

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and

100

, respectively. The time required for a current of

3 amp

to deposit a

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thick layer of the same metal on an area of

80 {cm}^{2}

is closest to

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Chemistry>Physical Chemistry>Electrochemistry>Electrolytic cells

Calculate the molarity of a solution containing

5 g

N a O H

dissolved in the product of a

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current for

595.1

hours.

(Assume

1 F = 96500 C / m o l

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40 g m o l^{- 1}

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MEDIUM

Chemistry>Physical Chemistry>Electrochemistry>Electrolytic cells

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values,

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MEDIUM

Chemistry>Physical Chemistry>Electrochemistry>Electrolytic cells

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amperes for

20

minutes. What mass of

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Chemistry>Physical Chemistry>Electrochemistry>Electrolytic cells

A solution of

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Faraday electricity. How many mole of

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A certain metal salt solutions is electrolysed in series with a silver coulometer. The weights of silver and the metal deposited are 0.5094 g and 0.2653 g. Calculate the valency of the metal if its atomic weight is nearly that of silver.

Important Questions on Electrochemistry

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